Systems and methods for providing dynamic vacuum pressure in an articulated arm

ABSTRACT

A system is disclosed for providing dynamic vacuum control to an end effector of an articulated arm. The system includes a first vacuum source for providing a first vacuum pressure with a first maximum air flow rate, and a second vacuum source for providing a second vacuum pressure with a second maximum air flow rate, wherein the second vacuum pressure is higher than the first vacuum pressure and wherein the second maximum air flow rate is greater than the first maximum air flow rate.

PRIORITY

The present application claims priority to U.S. Provisional PatentApplication Ser. No. 62/215,489 filed Sep. 8, 2015 and U.S. ProvisionalPatent Application Ser. No. 62/262,136 filed Dec. 2, 2015, thedisclosures of which are hereby incorporate by reference in theirentireties.

BACKGROUND

The invention generally relates to robotic systems, and relates inparticular to robotic systems having an articulated arm with an endeffector that employs vacuum pressure to engage objects in theenvironment.

Most vacuum grippers employ vacuum pressures well below 50% ofatmospheric pressure, and are referred to herein as high vacuum. Atypical source for a high vacuum gripper is a Venturi ejector, whichproduces high vacuum but low maximum air flow. Because of the low flow,it is essential to get a good seal between a vacuum gripper and anobject, and it is also important to minimize the volume to be evacuated.

Suppliers of ejectors and related system components include VacconCompany, Inc. of Medway, Mass., Festo US Corporation of Hauppauge, N.Y.,Schmalz, Inc. of Raleigh, N.C. and others. In some instances where agood seal is not possible, some systems use high flow devices. Typicalhigh flow devices are air amplifiers and blowers, which produce thedesired flows, but cannot produce the high vacuum of a high vacuumsource. High flow sources include the side-channel blowers supplied byElmo Rietschle of Gardner, Denver, Inc. of Quincy, Ill., Fuji ElectricCorporation of America of Edison, N.J., and Schmalz, Inc. of Raleigh,N.C.. It is also possible to use air amplifiers as supplied by EDCO USAof Fenton, Mo. and EXAIR Corporation of Cincinnati, Ohio. Multistageejectors are also known to be used to evacuate a large volume morequickly, wherein each stage provides higher levels of flow but lowerlevels of vacuum.

Despite the variety of vacuum systems, however, there remains a need foran end effector in a robotic system that is able to accommodate a widevariety of applications involving engaging a variety of types of items.There is further a need for an end effector that is able to high flowvacuum using a gripper that is able to handle a wide variety of objects.

SUMMARY

In accordance with an embodiment, the invention provides a system forproviding dynamic vacuum control to an end effector of an articulatedarm. The system includes a first vacuum source for providing a firstvacuum pressure with a first maximum air flow rate, and a second vacuumsource for providing a second vacuum pressure with a second maximum airflow rate. The second vacuum pressure is higher than the first vacuumpressure and wherein the second maximum air flow rate is greater thanthe first maximum air flow rate.

In accordance with another embodiment, the invention provides a methodof providing a dynamic vacuum source for an end effector. The methodincludes the steps of providing at the end effector a first vacuumhaving first vacuum pressure and a first vacuum flow, and switching thedynamic vacuum source to provide at the end effector a second vacuumhaving a second vacuum pressure and a second vacuum flow. The secondvacuum pressure is higher than the first vacuum pressure, and the secondvacuum flow is greater than the first vacuum flow.

In accordance with a further embodiment, the invention provides a systemfor providing vacuum control to an end effector of an articulated arm.The system includes a vacuum source for providing a vacuum pressure at aflow rate to the end effector, and the end effector includes a coverthat includes an opening that varies significantly in radius from acenter of the cover.

BRIEF DESCRIPTION OF THE DRAWINGS

The following description may be further understood with reference tothe accompanying drawings in which:

FIG. 1 shows an illustrative block diagrammatic view of a system inaccordance with an embodiment of the present invention;

FIG. 2 shows an illustrative diagrammatic view of an example of a systemof FIG. 1;

FIG. 3 shows an illustrative diagrammatic view of a system in accordancewith another embodiment of the present invention;

FIG. 4 shows an illustrative diagrammatic view of a system in accordancewith an embodiment of the present invention employing a high vacuumsource;

FIG. 5 shows an illustrative diagrammatic view of a system in accordancewith anther embodiment of the present invention employing a high flowsource;

FIG. 6 shows an illustrative diagrammatic view of a detection systemtogether with an end effector of a system of an embodiment of thepresent invention;

FIGS. 7A and 7B show an illustrative flowchart showing a process inaccordance with an embodiment of the present invention;

FIGS. 8A and 8B show illustrative diagrammatic views of an end effectorcover for use in a system of an embodiment of the present invention;

FIG. 9 shows an illustrative diagrammatic view of an end effector of anembodiment of the invention engaging an object;

FIGS. 10A-10D show illustrative diagrammatic views of other covers foruse with end effectors of systems of further embodiments of the presentinvention;

FIGS. 11A and 11B show illustrative diagrammatic views of an endeffector in a system of an embodiment of the present invention engaginga relatively light object;

FIGS. 12A and 12B show illustrative diagrammatic views of an endeffector in a system of an embodiment of the present invention engaginga relatively heavy object; and

FIGS. 13A and 13B show illustrative diagrammatic views of an endeffector in a system of an embodiment of the present invention engagingan object that presents an unbalanced load;

The drawings are shown for illustrative purposes only.

DETAILED DESCRIPTION

In accordance with an embodiment, the invention provides a hybrid highflow/high vacuum gripper that can grip a broader set of objects thangrippers based on either high flow or high vacuum alone. Previousdesigns are usually designed for a particular object. When a good sealbetween vacuum cup and object is possible, a high vacuum device such asa Venturi ejector is typically employed. When a good seal is notpossible because of object surface irregularities or porosity, a highflow device such as a regenerative blower is typically employed. Thehybrid gripper of an embodiment of the invention, uses either highvacuum or high flow, selected in real time to provide the most effectivegrip for the object, object pose, and surrounding context.

In various embodiments, therefore, the invention provides a grippersystem that combines multiple sources of vacuum, selecting the source inreal time. The invention provides, in an embodiment, a gripper systemthat switches from a high flow source to a high vacuum source as thepressure drops below the level sustainable by the high flow source, anda gripper system comprising a high flow source with a multistageejector, so that the non-return valve integrated in the multistageejector provides a selection mechanism in accordance with furtherembodiments.

A general approach to a vacuum gripper design, is to characterize theobject in question and select the catalog gripper, vacuum source, andother components best suited to the object. Many device suppliers andintegrators offer application engineering services to assist inselection of proper components. These options are exercised at systemdesign time however, and result in a system committed to grasp aspecific object, or in some instances a few objects.

There are be numerous applications for a gripping system that couldhandle a broad variety of objects, varying in size, weight, and surfaceproperties. The invention provides an approach to address this need byintroducing a mechanism to select between a high flow source and a highvacuum source, depending on the present situation.

FIG. 1, for example, shows a system 10 in accordance with an embodimentof the present invention in which a high vacuum source 12 is provided aswell as a high flow source 14 and a release source 16 that are eachcoupled to a selection unit 18, that is coupled to an end effector 20.The selection unit 18 selects between the high vacuum source 12, highflow source 14 and the release source 16 for providing any of highvacuum, vacuum with high flow, or a release flow to the end effector.FIG. 1 therefore shows a general form of the invention, comprisingmechanisms for producing high vacuum and high flow, a release sourceproviding either atmospheric pressure via a vent or high pressure (blowoff) via a compressor or reservoir, and a mechanism for selecting thesource best suited to the present situation.

In accordance with certain embodiments, therefore, the inventionprovides a system for providing dynamic vacuum control to an endeffector of an articulated arm. The system includes a first vacuumsource for providing a first vacuum pressure with a first maximum airflow rate; and a second vacuum source for providing a second vacuumpressure with a second maximum air flow rate, wherein the second vacuumpressure is higher than the first vacuum pressure and wherein the secondmaximum air flow rate is greater than the first maximum air flow rate.The flow rates are characterized as maximum air flow rates because, whenan object is engaged at an end effector, the flow rate may dropsignificantly.

In other embodiments, the invention provides a method for providing avacuum at an end effector on an articulated arm. The method includes thesteps of providing a first vacuum at the end effector at a first vacuumpressure with a first maximum air flow rate, and changing the vacuum atthe end effector to a second vacuum with a second vacuum pressure and asecond maximum air flow rate.

The selection mechanism may include a set of pneumatic valves driven byan estimated task state, based for example, in part, on sensor inputinformation. The selection mechanism may also select a vent or blow-offsource to release a part. In certain cases, the selection mechanism maybe based in part on a non-return valve (see FIG. 2), in other cases, anon-return valve integrated in a multistage ejector, with an additionalvalve to select a vent or blow-off source in order to release a part(see FIG. 3).

In particular, FIG. 2 shows a system in accordance with an embodiment ofthe invention that includes a compressor 30 that is coupled to anejector 32 to provide a high vacuum source that is coupled to a solenoidvalve 34. A blower 36 is also coupled to the solenoid valve 34 via anon-return valve 38, and the blower 36 provides a vacuum source with ahigh maximum flow rate. A vent or blow-off source is also provided tothe solenoid valve 34, the output of which is provided to an endeffector 40. The system therefore, provides the ejector 32 as the highvacuum source, the regenerative blower 36 as the high flow source, thenon-return valve 38 as a passive selection mechanism, and the solenoidvalve 34 connecting the effector to the release source, either vent orblow-off.

The vacuum pressure provided by the ejector 32 may be, for example, atleast about about 90,000 Pascals below atmospheric and the vacuumpressure provided by the blower 36 may be only no more than about 25,000Pascals below atmospheric, and no more than about 50,000 Pascals belowatmospheric in further embodiments. The vacuum pressure provided by theblower 36 is therefore higher than the vacuum pressure provided by theejector 32. The maximum air flow rate of the ejector may be, forexample, no more than about 5 cubic feet per minute (e.g., 1-2 cubicfeet per minute), and the maximum air flow rate of the blower may be,for example at least about 100 cubic feet per minute (e.g., 130-140cubic feet per minute).

FIG. 3, for example, shows another embodiment of the invention thatincludes a multi-stage ejector 50, a compressor 52 and a blower 54. Themulti-stage ejector 50 provides a dynamic vacuum pressure to a solenoidvalve 56 that may switch between providing an end effector 58 witheither the dynamic vacuum pressure and a vent or blow-off positive airpressure source. The system uses the non-return valve of a multi-stageejector as the selection mechanism. In particular, the multi-stageejector includes a series of apertures of increasing size (e.g., left toright as illustrated in FIG. 3). At first, the largest aperture isdominant, evacuating air quickly until the air pressure drops, then thenext size aperture become dominant until air pressure drops further, andfinally the smallest size aperture becomes dominant. The system of FIG.3, however, includes check valves on the larger aperture paths as wellas the blower 54 to keep the air flow path from defeating the highvacuum, smallest aperture, in the event of a good seal.

For example, with reference to FIG. 4, if a good seal is formed betweenan end effector 60 (which may for example, be a tubular or conicalshaped bellows) and an object 62 on an articulated arm 64, then thevacuum pressure provided by the smaller aperture in the multi-stageejector 50 remains dominant because the non-return valves in themulti-stage ejector 50 prevent air flow backwards through the blower 54.This will provide that the grasp of object 72 will be maintained by thelower pressure vacuum with a lower maximum air flow rate.

With reference to FIG. 5, if a good seal is not formed between an endeffector 70 and an irregularly shaped object 72 on an articulated arm74, then the blower 54 will dominate maintaining a high flow,maintaining a grasp of object 72 with a higher maximum air flow rate.

With reference to FIG. 6, in accordance with a further embodiment, thesystem may include an articulated arm 80 to which is attached an endeffector 82, again, which may be a tubular or conical shaped bellows.The end effector 82 also includes a sensor 84 that includes anattachment band 86 on the bellows, as well as a bracket 88 attached tomagnetic field sensor 90, and a magnet 92 is mounted on the articulatedarm 80. As the bellows moves in any of three directions (e.g., towardand away from the articulated arm as shown diagrammatically at A, indirections transverse to the direction A as shown at B, and directionspartially transverse to the direction A as shown at C. The magneticfield sensor 90 may communicate (e.g., wirelessly) with a controller 90,which may also communicate with a flow monitor 94 to determine whether ahigh flow grasp of an object is sufficient for continued grasp andtransport as discussed further below. In certain embodiment, forexample, the system may return the object if the air flow isinsufficient to carry the load, or may increase the air flow to safelymaintain the load.

FIGS. 7A and 7B show the process steps of a system in accordance with anembodiment of the present invention, wherein the process begins (step1000) by applying a high flow/low vacuum source to an end effector (step1002). The end effector is then applied to an object to be moved (step1004). Generally, the system begins and continues lifting the objectuntil the end of the lifting routine (step 1006), begins and continuesmoving the object until the end of the moving routine (step 1008), thenapplies a positive air pressure force to urge the object from the endeffector (step 1010) and then ends (step 1012). If the air flow at theend effector at any points falls too low, then the system mayautomatically switch to a high vacuum/low flow source as discussedabove. In certain embodiments, sensor(s) may be employed to eitherconfirm that such a switch is need and/or has been made. In furtherembodiments, the sensor output(s) may drive a mechanical switch tochange vacuum sources.

For example, FIG. 7B also shows that once the end effector is applied toan object (step 1004), a subroutine is a called (at A to B) that firstreads the one or more sensors (step 1014). If any of the one or moresensor output(s) is outside of a threshold (step 1016), then the systemmay confirm that the system has switched to a high vacuum/low flowsource (step 1018). As noted above, in certain embodiments, the sensoroutput(s) may drive a mechanical switch the changes the vacuum at theend effector to be a high vacuum/low flow source (step 1018). Thensystem then returns to the step from which it was called. Duringexecution of the beginning and continuing lifting until end (step 1006),the system continuously calls the subroutine (A to B) until the objectis fully lifted. The system then moves to the step of beginning andcontinuing moving the object until end (step 1008), and during executionof this action, the system continuously calls the subroutine (A to B)until the object is fully moved.

The system may therefore, automatically switch between high flow/lowvacuum and low flow/high vacuum sources. In certain embodiments, thesystem may employ sensors to monitor and confirm that such switching isneeded and is performed. As noted, the system may also effect theswitching responsive to the one or more sensor output(s).

During low vacuum/high flow use, a specialized end effector may be usedthat provides improved grasping of long narrow objects. Certain grippersthat are designed for high flow use to acquire and hold an objectgenerally require large apertures in order to obtain an air flow ratethat is high enough to be useful for object acquisition. One drawback ofsome such grippers in certain applications, is that the object to beacquired may be small, not so small that each of its dimensions issmaller than the high flow opening, but small enough that certain of anobject's dimensions is smaller than the opening. For example, longnarrow objects such as pens, pencils etc., do not occlude enough of thehigh flow opening to generate sufficient negative forces to hold theobject securely.

In accordance with an embodiment therefore, the invention provides aspecialized cover for use with a high flow vacuum gripper. In particularand as shown in FIGS. 8A (articulated arm facing side) and 8B (objectfacing side), such a cover 100 may include a proximal back side 102 thatdoes not permit air to flow through the material, and distal front side104 for engaging objects that is formed of a foam material. Slitopenings 106 in form of a star or asterisk shape are provided throughthe material in this example. During use, elongated objects may bereceived along opposing slit openings and held by the foam material.

FIG. 9, for example, shows an elongated object 96 being held against thefoam material 104 of a cover 100 that is coupled to the end effector 82.While the elongated object 96 covers some of the opening provided by theslits 106, other portions 108 of the opening provided by the slits 106are remain open. The pattern cut into the material allows for enougharea to still obtain a relatively high flow, while providing a number orpositions (or orientations) for a long, thin object to block (and thusbe held by) a sufficiently high percentage of the air flow.

The compliant foam on the surface 104 contacts the object to beacquired, giving the gripper some compliance while also acting to sealthe aperture around the object as the foam is compressed and the highflow vacuum is applied. The aperture cover therefore allows a high flowgripper to effectively pick up long narrow objects with an easy toattach cover that may be held in a tool changer and added or removedfrom the gripper autonomously during real-time operation

In accordance with various embodiments, the cover 100 may be applied tothe end effector by a human worker into a friction fitting on the end ofthe end effector, or in certain embodiments, the cover may be providedin a bank of available end effector attachments that the articulated armmay be programmed to engage as needed, and disengage when finished,e.g., using forced positive air pressure and/or a grasping device thatsecures the end effector attachment for release from the articulatedarm.

A system is therefore provided in an embodiment, for providing vacuumcontrol to an end effector of an articulated arm, where the systemincludes a vacuum source for providing a vacuum pressure at a high flowrate to the end effector, and the end effector includes a cover thatincludes an opening that varies significantly in radius from a center ofthe cover. The opening may include finger openings that extend radiallyfrom the center of the opening. The opening may be generally star shapedor asterisk shaped. The cover may include compliant foam on a distalside of the cover that engages an object to be grasped, and an air flowresistant material on a proximal side of the cover. The vacuum pressuremay be no more than about 50,000 Pascals below atmospheric, and the airflow rate may be at least about 100 cubic feet per minute.

Covers with other types of openings are shown in FIG. 10A-10D. FIG. 10A,for example, shows a cover 120 that includes slit openings 122. FIG. 10Bshows a cover 130 that includes different sixed square openings 132,134. Cover 140 shown in FIG. 10C includes small circular openings 142,and cover 150 shown in FIG. 10D includes differently shaped openings 152and 154. In each of the covers 100, 120, 130, 140 and 150, a compliantfoam surface may face the object to be acquired, and more area of thecover is provided to be open closer to the center of the cover withrespect to the outer periphery of each cover. For example, in the cover100, the center of the asterisk shape is most open. In the cover 120,the larger slits are provided in the center. In the cover 130, thelarger square openings are provided in the center. In the cover 140, thegreater concentration of the circular openings is provided in thecenter, and in the cover 150, the lager shape 154 is provided in thecenter.

Systems in accordance with certain embodiments of the invention are ableto monitor flow within the end effector as well as the weight andbalance of an object being grasped. FIGS. 11A and 11B show an object 160being lifted from a surface 162 by the end effector 82 that includes theload detection device of FIG. 6. The high flow/low vacuum source isinitially applied. Upon engaging the object 160, the system notes theposition of the detection device and the level of flow (F₁) within theend effector as well as the vacuum pressure (P₁) and load (W₁) as shownin FIG. 11A. Once the object 160 is lifted (FIG. 11B), the system notesthe change in the amount of flow (ΔF₁). In this example, the loadprovided by the object 160 is relatively light (ΔW₁), and a smallvariation (ΔF₁) in flow may (when considering the load and aperturesize) may be accepted, permitting the source to remain high flow/lowvacuum. FIGS. 12A and 12B, however, show the end effector lifting aheavy object with a more flat surface.

FIGS. 12A and 12B show an object 170 being lifted from a surface 172 bythe end effector 82 that includes the load detection device of FIG. 6.The high flow/low vacuum source is initially applied. Upon engaging theobject 170, the system notes the position of the detection device andthe level of flow (F₂) within the end effector as well as the vacuumpressure (P₂) and load (W₂) as shown in FIG. 12A. Once the object 170 islifted (FIG. 12B), the system notes the change in the amount of flow(ΔF₂). As noted above, in this example, the object 170 is heavy (ΔW₂),presenting a higher load. The system will evaluate the load incombination with the flow (F₂) and pressure (P₂) as well as the changein flow (ΔF₂) and change in pressure (ΔP₂) to assess the grasp of theobject. The system may automatically switch to the high vacuum, low flowvacuum source as discussed above.

The system may also detect whether a load is not sufficiently balanced.FIGS. 13A and 13B show an object 180 being lifted from a surface 182 bythe end effector 82 that includes the load detection device of FIG. 6.The high flow/low vacuum source is initially applied. Upon engaging theobject 180, the system notes the position of the detection device andthe level of flow (F₃) within the end effector as well as the vacuumpressure (P₃) and load (W₃) as shown in FIG. 13A. Once the object 180 islifted (FIG. 13B), the system notes the change in the amount of flow(ΔF₃). In this example, the object 180 presents a non-balanced load(ΔW₃). The system will evaluate the load in combination with the flow(F₃) and pressure (P₃) as well as the change in flow (ΔF₃) and change inpressure (ΔP₃) to assess the grasp of the object. The system mayautomatically switch to the high vacuum, low flow vacuum source asdiscussed above. In each of the examples of FIGS. 11A-13B, any of vacuumpressure sensors, flow sensors, weight and balance detections may beemployed to monitor the status of the end effector and the load, and theswitching may occur automatically, or by analysis of the above values.

In accordance with certain embodiments, the system may switch between ahigh vacuum, low flow source and a low vacuum high flow source dependingon input from the sensor 84. For example, if an object is engaged suchthat the bellows is substantially moved in either directions B or C,then the system may elect to maintain the high vacuum, low flow source,or may elect to return the object without moving the object.

During low vacuum/high flow use, a specialized end effector may be usedthat provides improved grasping of long narrow objects. Certain grippersthat are designed for high flow use to acquire and hold an objectgenerally require large apertures in order to obtain an air flow ratethat is high enough to be useful for object acquisition. One drawback ofsome such grippers in certain applications, is that the object to beacquired may be small, not so small that each of its dimensions issmaller than the high flow opening, but small enough that certain of anobject's dimensions is smaller than the opening. For example, longnarrow objects such as pens, pencils etc., do not occlude enough of thehigh flow opening to generate sufficient negative forces to hold theobject securely.

In accordance with an embodiment, therefore, the system provides vacuumcontrol to an end effector of an articulated arm, where the systemincludes a vacuum source for providing a vacuum pressure at a flow rateto the end effector, and the end effector includes a cover that includesan opening that varies significantly in radius from a center of thecover. The opening may include finger openings that extend radially fromthe center of the opening. The opening may be generally star shaped orasterisk shaped. The cover may include compliant foam on a distal sideof the cover that engages an object to be grasped, and an air flowresistant material on a proximal side of the cover. The vacuum pressuremay be no more than about 25,000 Pascals below atmospheric, and the airflow rate may be at least about 100 cubic feet per minute to provide ahigh flow/low vacuum source. The cover may include an opening thatvaries significantly in radius from a center of the cover, and theopening may include finger openings that extend radially from the centerof the opening, and for example, may be generally star shaped orasterisk shaped.

Those skilled in the art will appreciate that numerous modifications andvariations may be made to the above disclosed embodiments withoutdeparting from the spirit and scope of the present invention.

What is claimed is:
 1. A system for providing dynamic vacuum control toan end effector of an articulated arm, said system comprising: a firstvacuum source for providing a first vacuum pressure with a first maximumair flow rate; and a second vacuum source for providing a second vacuumpressure with a second maximum air flow rate, wherein the second vacuumpressure is higher than the first vacuum pressure and wherein the secondmaximum air flow rate is greater than the first maximum air flow rate.2. The system as claimed in claim 1, wherein said first vacuum pressureis at least about 90,000 Pascals below atmospheric, and said secondvacuum pressure is no more than about 50,000 Pascals below atmospheric.3. The system as claimed in claim 1, wherein said first maximum air flowrate is at most about 5 cubic feet per minute, and said second maximumair flow rate is at least about 100 cubic feet per minute.
 4. The systemas claimed in claim 1, wherein the system further includes a switch forproviding either the first vacuum pressure or the second vacuum pressureat the end effector responsive to a signal from at least one sensor. 5.The system as claimed in claim 4, wherein the switch is provided by anon-return valve.
 6. The system as claimed in claim 4, wherein the atleast one sensor is a flow sensor.
 7. The system as claimed in claim 4,wherein the at least one sensor is a pressure sensor.
 8. The system asclaimed in claim 1, wherein the first vacuum source and the secondvacuum source are provided by a multistage ejector.
 9. The system asclaimed in claim 8, wherein the system includes a non-return valve inthe multistage ejector for switching between providing the first vacuumpressure and the second vacuum pressure.
 10. The system as claimed inclaim 1, wherein the system further includes a release source forproviding positive pressure at the end effector for ejecting an objectfrom the end effector.
 11. A method of providing a dynamic vacuum sourcefor an end effector, said method comprising the steps of: providing atthe end effector a first vacuum having first vacuum pressure and a firstvacuum flow; and switching the dynamic vacuum source to provide at theend effector a second vacuum having a second vacuum pressure and asecond vacuum flow, said second vacuum pressure being higher than thefirst vacuum pressure, and the second vacuum flow being greater than thefirst vacuum flow.
 12. The method as claimed in claim 11, wherein saidfirst vacuum pressure is at least about 90,000 Pascals belowatmospheric, and said second vacuum pressure is no more than about50,000 Pascals below atmospheric.
 13. The method as claimed in claim 11,wherein said first maximum air flow rate is at most about 5 cubic feetper minute, and said second maximum air flow rate is at least about 100cubic feet per minute.
 14. The method as claimed in claim 11, whereinthe step of switching the dynamic vacuum source occurs automaticallywithout any input commands.
 15. The method as claimed in claim 12,wherein the step of switching the dynamic vacuum source occurs by use ofa non-return valve.
 16. The method as claimed in claim 12, wherein thestep of switching the dynamic vacuum source occurs by a processoractuated switch.
 17. The method as claimed in claim 11, wherein themethod further includes the step of confirming, using an output of atleast one sensor, that the dynamic vacuum source has switched to thesecond vacuum pressure that is higher than the first vacuum pressure,and that has a second vacuum flow that is greater than the first vacuumflow.
 16. The method as claimed in claim 11, wherein the method occursduring application of the end effector to an object to be grasped. 17.The method as claimed in claim 11, wherein the method occurs during aprocess of lifting an object with the end effector.
 18. The method asclaimed in claim 11, wherein the method occurs during a process ofmoving an object with the end effector.
 19. The method as claimed inclaim 11, wherein the method further includes the method of providing apositive air pressure to the end effector to urge an object from the endeffector.
 20. A system for providing vacuum control to an end effectorof an articulated arm, said system comprising a vacuum source forproviding a vacuum pressure at a flow rate to the end effector, said endeffector including a cover that includes an opening that variessignificantly in radius from a center of the cover.
 21. The system asclaimed in claim 20, wherein the opening includes finger openings thatextend radially from the center of the opening.
 22. The system asclaimed in claim 20, wherein the cover includes an opening that variessignificantly in radius from a center of the cover.